Replication Package — Paying It Forward: Public Opinion Effects of U.S. COVID-19 Vaccine Aid in South Korea

This package contains the data and code to reproduce all empirical results in the manuscript.

Contents
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- bae_lee_replication.dta — Analysis dataset (N=3,459). Includes unique respondent identifier ID.
- bae_lee_codebook.csv — Variable codebook (name, label, type, N, missing, summary stats).
- bae_lee_replication.do — Stata script to generate regression results and export tables.

Software
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- Stata 16 or later (tested with Stata 17)
- User-written package: estout (for eststo / esttab)
  Install via:
    ssc install estout, replace

Quick Start
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1. Open Stata and set the working directory to the replication folder:
     cd "PATH/TO/REPLICATION/FOLDER"
2. Install the required package:
     ssc install estout, replace
3. Run the replication script:
     do "bae_lee_replication.do"

What the script does
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The .do file:
- Constructs key variables (e.g., jans, othervac, jans_elig, newvacc, and first-difference outcomes).
- Runs the main specifications for all results tables.
- Produces descriptive statistics for Table 2.
- Exports all tables as .csv files to the /output folder.

Exported files correspond to manuscript tables:
- T3.csv — Table 3
- T4.csv — Table 4
- T5.csv — Table 5
- aT1_retention.csv — Appendix Table A1
- aT2_view_US.csv — Appendix Table A2
- aT4_origin_test.csv — Appendix Tables A4
- aT5_difference.csv — Appendix Table A5

Reproducibility checklist (POQ compliance)
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- Data file present (.dta) with unique respondent IDs.
- Codebook present (.csv) with full variable metadata.
- Script reproduces all main and appendix tables; outputs saved in /output.
- All analyses run from a single .do file; no external merges.
- Required Stata package: estout.

Variable notes (selected)
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- ID — unique respondent identifier.
- w1_y1, w2_y1 — favorability toward the US (1–7 scale).
- w1_y2, w2_y2 — support for vaccine aid (1–7 scale); wave 1 measured for a subset.
- vactype — vaccine type code.
- w1_vacc, w2_vaccf — vaccination status by wave.
- usinfo — information-treatment indicator in wave 2.

Full list in bae_lee_codebook.csv.

Citation
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If you use these data or code, please cite:
Joonbum Bae and Changkeun Lee, "Paying It Forward: Public Opinion Effects of U.S. COVID-19 Vaccine Aid in South Korea," Public Opinion Quarterly, forthcoming.

Last updated: 2025-08-10
